Mainframes

• An extremely large, powerful computer
• Capable of processing thousands of transactions a second
• Can store terabytes of information on the mainframe
• Usually used to support extremely large amounts of users

Client Servers

• Distributed system with both client and server software
• Client sends requests to the server
• Server processes requests from many clients at once
• For example, clients can be web browsers
  • The browser could access a bank server and access account information

Comparison

• Mainframes are more powerful and scalable compared to Client Servers
• Mainframes save energy
  • All the computing is centralized into the mainframe
  • Client servers have computations happen on every client
• In regards to price
  • Mainframes are extremely expensive
  • Mainframes can cost upwards of $1,000,000
  • Client Servers, while expensive, can be much cheaper
• Mainframes are better suited to for large-scale businesses and organizations
  • Any company that processes millions of transactions a day should be utilizing the power of mainframes
  • A client server would not be able to keep up as well
• Software Support
  • Client servers are up to date with the latest technology
  • Mainframes usually only support COBOL and Java
  • Client servers can support virtually every language you could want to use
• Client servers put more computational stress on the clients
  • Mainframes take care of all of the computations on its own
• Mainframes are more reliable than client servers
  • Mainframes are required to be up 99.9999% of the time
  • It's difficult to create a client server with such reliability
• Client servers are easier to set up